This invention relates generally to apparatus for slicing food products into strips, especially the slicing of potatoes into strips suitable for processing as "french fries".
Heretofore, various slicing apparatus have been used to slice potatoes into elongate strips suitable for processing as french fries. One such apparatus, sometimes referred to as a "box cutter", comprises a series of perpendicularly intersecting, straight-edged blades to form a grid of box like cutters. The grid is forced mechanically through the potato, which is held stationary, thereby slicing the potato into strips of square cross section. A relatively large force is required to force the grid through the potato. Also, as the blades slice through the potato, they cause small breaks and fractures in the cut potato surfaces, making the resulting strips more fragile during subsequent handling and processing. The damage to the potato surfaces during slicing is sometimes referred to as "feathering". Examples of box cutters are shown in Babigan U.S. Pat. No. 3,391,005 (FIGS. 11-15).
Another prior potato slicing apparatus is disclosed in Lamb et al., U.S. Pat. No. 3,116,772. In contrast to the box cutter just described, this patent discloses a system in which moving potatoes are forced through a stationary grid or matrix of sharpened blades. The potatoes are carried by conduit in a fast moving fluid stream and delivered individually and sequentially to the slicing apparatus which is aligned with the flow path of the potatoes. Each potato is forced through the slicing apparatus by the hydraulic flow and its own momentum, and is thereby cut into strips.
In one form FIGS. (2-6), the slicing apparatus includes a large box cutter for cutting away the outermost slabs of the potatoes and five crossed blades mounted within the box cutter downstream of its mouth. The five crossed blades are mounted in transversely spaced, axially staggered pairs, with the exception of one single, centrally located blade. As the potato is forced through the slicing apparatus, the outermost portions of the potato are progressively sliced away.
A second form of the slicing apparatus, shown in FIG. 18, is similar to the one just described, except that the blades are elongate and slotted to intersect one another and provide transverse support. As with the first form, both sets of parallel blades are axially staggered and arranged such that the outermost portions of the potato are progressively sliced away and eventually cut into strips.
Although both foregoing slicing apparatus work reasonably well, some binding of the potato occurs due to frictional engagement with the blades and "blade pinching". Blade pinching occurs when a sliced section of the potato is compressively forced between two blades. The tendency of the potato to bind is more acute with the blade assembly of FIG. 18, since it is designed to slice the potato into 1/4 inch "shoe string" potato strips and hence has more blades (than the assembly of FIGS. 2-6) slicing through the potato.
Yet another potato slicing apparatus, intended to be an improvement of the one shown in U.S. Pat. No. 3,116,772, is disclosed in Hodges et al. U.S. Pat. No. 4,135,002. It has a plurality of intersecting, axially staggered blades of chevron configuration, which are arranged in a nested, pyramidal formation. The apex of the pyramidal formation and apexes of the blades themselves point in the direction of the approaching potato, which is carried in a fluid stream. This arrangement is intended to reduce binding by facilitating the use of thinner blades and permitting the incised potato portions to spread out upon slicing.
However, it is believed that some binding will still occur for two reasons. First, virtually all incised potato portions are frictionally engaged on opposite sides by adjacent, transversely spaced blades slicing through each potato portion. Second, such blades will exert a compressive force on the potato portion as it travels therebetween. Although each incised potato portion is permitted to spread somewhat during slicing to reduce binding, it is believed that thickness dimension of the blades will still cause some compression of the potato portion as it travels therebetween. Further, unless the potatoes are perfectly aligned with the apex of the blade arrangement, they will have a tendency to veer to one side upon striking the leading blades, or to turn or tumble slightly, thereby detracting from the quality of the cut. Ideally, the potatoes should remain aligned with and follow the axial centerline of the slicing apparatus to optimize cutting quality and effectiveness.
Accordingly, there remains a need for an improved blade assembly for slicing potatoes and the like into strips, which will minimize binding, reduce feathering, slice through the potato with minimal resistance, minimize the tendency of the potato to turn or tumble upon striking the blade assembly, and at the same time keep the potatoes axially aligned as they are sliced.
It is therefore one object of the present invention to provide an improved blade assembly for slicing potatoes and the like which improves the quality and effectiveness of the slicing operation.
Another object of the present invention is to provide a blade assembly as aforesaid which reduces feathering, thereby making the resulting cut strips less fragile and easier to handle and process further.
A further object of the present invention is to provide a blade assembly as aforesaid which reduces binding and hence requires less force to slice the potato into strips.
Yet another object of the present invention is to provide a self-centering blade assembly which, during slicing, keeps the potatoes centered and reduces the tendency of the potatoes to turn or tumble.
Still another object of the present invention is to provide a blade assembly having longer lasting knife blades.
Other objects of the present invention will be apparent from the drawings and following detailed description.